Alternating oculomotor paralysis, or Weber's syndrome, is characterized by palsy of the third nerve on one side with contralateral paralysis of the body. The lesion responsible for such a syndrome is located in the anterior aspects of the midbrain and involves the corticospinal path (pyramidal tract) and the fibers of the third nerve that traverse it. Alternating oculomotor paralysis may also occur in lesions of the middle fossa.
In this paper, I shall endeavor to show that acute traumatic middle meningeal hemorrhage may give rise to typical alternating oculomotor paralysis by virtue of the fact that the extension of the dissecting clot into the base of the middle fossa causes an oculomotor palsy, and its pressure against the convexity of the hemisphere is productive of contralateral paralysis of the body. From the surgical standpoint it is important to localize such a lesion accurately; otherwise, the treatment instituted may not alleviate
GURDJIAN ES. ALTERNATING OCULOMOTOR PARALYSIS IN TRAUMATIC MIDDLE MENINGEAL HEMORRHAGE. Arch NeurPsych. 1932;28(1):26-36. doi:10.1001/archneurpsyc.1932.02240010034002